Friday, the day of gathering

Islam adopts a middle course between materialism and asceticism, the physical and spiritual, considers the voluntary rejection of the good and lawful pleasures of life as a transgression, just as the excessiveness in the pursuit of worldly objectives, without any consideration for their higher purpose as a sin 

24:37"Men whom neither merchandise nor selling diverts from the remembrance of Allah and the keeping up of prayer and the giving of poor-rate; they fear a day in which the hearts and eyes shall turn about". 

That balanced mindframe is reflected even in the etiquette to adopt during prayers, where one is to keep his eyes open and thus maintain a connection with the world even in the performance of the prescribed spiritual duties. Whenever it speaks of being benevolent, it also lays stress on not forgetting one's self or abandoning the lawful pleasures of the world, just as, contrary to the purely materialistic mosaic commandment of "be fruitful and multiply", almost every injunction related to materialism and the rightful enjoyment of this world's benefits comes with a reminder of the higher, lasting realities. It recognizes as well as answers and safeguards the legitimate needs of both aspects of man's being, tying together the material aspect, with the higher spiritual reality 

2:168,172,5:87-88,7:32,16:116,28:77"And seek by means of what Allah has given you the future abode, and do not neglect your portion of this world, and do good (to others) as Allah has done good to you"

 62:9-10"when the call is made for prayer on the day of gathering, then hasten to the remembrance of Allah and leave off selling..when the prayer is ended, then disperse abroad in the land and seek of Allah's grace". 

From a linguistic viewpoint, it is interesting noting the Quran's surgical use of words to produce maximum impact on its audience. In that verse from sura jumu'a, it doesnt command to leave off business in general, but specifically selling, which is the most relevant part of every business and the most sought after moment. Historically, the Arabs used to gather on that day to sell off their goods. This is reflected in the precise wordings of the verse. It doesnt call a scattered people to unite and pray in congregation, rather it calls people that are already assembled to leave that which they are busy with, in order to pray. As already noted, it speaks of selling specifically and that is because the Medinans were mainly farming communities and farmers tend to gather on a commonly agreed upon day so as to sell their produce. The Medina Jews, who formed a considerable part of the population, are also reported to have gathered on that day for similar purposes and because the next day was a holiday, the sabbath, during which all work had to stop. 

Jews and Christians have historically disagreed about their respective day. The former have been transgressing the Sabbath since its establishment under Moses, and the latter were split on whether to keep Shabbath or adopt Sunday as the day of gathering and prayer. This disagreement among Christians continues till this day. Allah graced the Muslims and bestowed Friday upon them only, as a reward for following the truth, and kept it away from the former transgressing nations 

"The Messenger of Allah said: 'Allah sent astray from Friday those who came before us, so the Jews had Saturday and the Christians had Sunday.." 

"..They disagreed and Allah guided us aright on whatever they disagreed regarding the truth. And it was this day of theirs about which they disagreed, but Allah guided us to it, and that is Friday for us..."

This command to pray on the day of gathering/yawm al jumua teaches first and foremost the correct balanced mindframe to have in this life, prioritizing the hereafter even at the most rewarding worldly moment, but without sacrificing the pursuit of material benefits altogether. Because of the instability of these early day of Islam, that day of gathering also acquired a political significance. By attending it, the worshipper declared his affiliation and dedication to the cause of the community. That is why it was traditionally the local leader who led the prayer. The case is different today where it is mainly, if only, religious figures that do so and thus the political connotation is no longer present.